1. Field:
The invention is in the field of rotary mills for milling grains into flour or similar products.
2. State of the Art:
Numerous mills have been designed for milling grains, such as wheat, into flour. One of the more commercially successful of these mills is described in U.S. Pat. No. 4,203,555. In that mill, rows of teeth on a rotor are interposed between rows of stationary teeth on a stator. The grain is milled by its impact with the teeth as it moves radially outwardly through the alternating rows of stationary and moving teeth. The innermost row of teeth are on the rotor and the control of the grind is achieved by controlling the amount of grain and air flow into the grain inlet of the mill through the use of an air bypass valve. With the bypass valve closed, all air and grain flows through the grain inlet. Maximum throughput and coarse grind result. Motor loading is maximum and motor speed minimum. As the air bypass is opened, there is more air flow with less grain throughput. Motor speed increases and a finer grind results.
The mills of the prior art, including that of U.S. Pat. No. 4,203,555, have problems obtaining a uniform grind and controlling the grind. There is also a problem with some of the prior art mills of having pieces of grain thrown out of the feed entrance of the mill when only a small amount of grain is left to be fed into the mill.